The present invention relates to post-mix beverage dispensers which are compact, portable and suitable for use in small offices or small dispensing volume locations.
A post-mix beverage dispenser generally includes a syrup package having a flow control tube therein which is vented to the atmosphere, as shown in U.S. Pat. No. 4,493,441, which is hereby incorporated by reference. However, since there are some problems as to sanitation and lack of constancy of the flow rate of syrup in this dispenser, it is proposed to use a hermetic package as a syrup package and to use the pressure of the CO.sub.2 from a CO.sub.2 cylinder to vent the syrup, as shown in U.S. patent application Ser. No. 07/332,982, filed Apr. 4, 1989. However, when the syrup package is empty and to be replaced with another new one, a valve should be manually switched to prevent the venting of the CO.sub.2.